Study Of Distribution Of The Heavy Metals From The Intertidal Sediments And Pollution Assessment Of The Metals From The Intertidal Zone In Jiaozhou Bay

Based on the total concentrations of six species of pollution metals (Zn, Cu, Cr, Cd, Pb, Hg)from the sediments , surface seawater and marine organisms of five kinds of intertidal zone of Jiaozhou Bay , the characteristics of distribution of the heavy metals from the sediments was discussed, further more, the polluted actuality of the intertidal sediments was assessed in the paper. The main experimental results are as follows:1. The distribution characteristics of the metals from the intertidal sediments of Jiaozhou Bay(1)The results shown that ,the available concentraion of Zn is ranged 53.88-143.21μg/g(dry weight), Cu is ranged 18.56-65.34μg/g(dry weight), Cr is ranged 10.82-105.49μg/g(dry weight), Pb is ranged 2.14-31.92μg/g(dry weight), Cd is ranged 0.04-0.836μg/g(dry weight), Hg is ranged 0.005-0.115μg/g(dry weight), Eh is ranged -307.9-84.4mV, pH is ranged 7.589-8.019, the sediment in Jiaozhou Bay is featured by reduction, so the sediment of Jiaozhou Bay deposied Well.(2)Along the intertidal zone,the lower of contents of heavy metal exponentially,the farther is from sewage sources.(3)The concentrations of heavy metal decrease inch by inch from high tidal flat to the middle and low intertidal zone. It is water dynamics that impact on the accumulation features of heavy metals of intertidal.(4)lt is Eh that impact on the vertical distribution of heavy metal over tidal flat. At boundary ofredox layer, there is the biggest enrichment of heavy metals. But the characteristic of distribution may be modified by plant activities in the tidal flat.2.The pollution assessment of the heavy metals from the intertidal sediments of Jiaozhou Bay(1)The heavy metals in intertidal sediment are mainly derived from river ,it also can be influenced by water dynamics.(2)The characteristics of distribution of the middle and bottom layer sediments are similar with the surface layer sediments.lt is shown that it is tide that importantly impact on the distribution of heavy metals in intertidal sediment of Jiaozhou Bay .So this paper assessed the heavy metals pollution only based on the surface layer sediments.(3)The assessment of Pj shows that the pollution of Cu is relatively serious , the pollution of Cr,, Zn and Cd is relatively lighter, Pb and Hg almost have no pollution. The assessment of SQJ shows that there is relatively serious pollution in Jiaozhou Bay except that of Hetao is relatively lighter,while the pollution of Jiaozhou Bay is relatively lighter by the assessment of RI .(4)The contents' order of indicator organism-sinonovacula constricta in Jiaozhou Bay is much lower than the criteria .The ability of enrichment of indicator organism in the following order: Cu>Zn>Cd>Cr>Pb>Hg, which is influenced by many factors such as position and organism variety. It shows that the values of Zn/Cd, Zn/Hg are also very useful for monitoring the environmental quality from the intertidal sediments of Jiaozhou Bay.Thus it can be seen that the pollution of the heavy metals in intertidal of Jiaozhou Bay is not serious.But the estuaries of Nvgukou and Dagu river are contaminated by heavy metals.Especially the estuary of Nvgukou is more serious,which is not fit to develop salt industry and fishery,but fit to establish Dock.With the increasing of the polluted water of Dagu river in Jiaozhou, the pollution of the west of JiaozhouBay is more serious.So we should strengthen the prevention of the intertidal of Jiaozhou Bay .